Basically, CGI.pm has everything you need for the "uploader" part. You don't show any code nor do you tell us where it failed for you, so we can't be of much help there. Adding the file (contents) to the database is then easily done using DBI.

You can use Image::Magick or the external convert utility (which often is easier available) or possibly Imager for resizing your image. It isn't that hard to write such a program.

This is not a script writing site. We will gladly help you with your problems, but we don't write complete programs unless they are particularly interesting.